CHICAGO HEIGHTS, Ill. (CBS) — High School students posed as tear-gassed NATO demonstrators on Wednesday as Franciscan Saint James Hospital in Chicago Heights drilled emergency teams who might be needed if protests get out of hand during the NATO summit in May and Chicago hospitals are overwhelmed.

About 30 Lincoln-Way North High School students wore makeup and white chemical suits as they pulled up to the hospital in a bus, so Saint James officials could test their decontamination procedures.

“We actually put makeup on them so that they looked like they were pale, or that they had lacerations,” hospital ambulance manager John Slykas said.

Franciscan Saint James also wanted to practice washing off pepper gel, in case riot teams use that instead of tear gas – which could infiltrate ventilation systems of downtown high rise apartments and buildings.

“We think that the city, during the NATO summit, is going to try to limit the use of tear gas, because of the ventilation systems in the high rises, and this was an agent that we really thought we were going to have to deal with,” Slykas said.

Pepper gel is basically a sticky form of pepper spray.

“Wash it off with, basically with soap and water,” Slykas said. “It can leave burns, it can leave eye abrasions, it can cause respiratory distress. So you just treat the symptoms.”

Slykas said staffers exceeded expectations, managing to decontaminate one person per minute, with the contaminated runoff collected for disposal by a hazardous waste service.

While Chicago is about 30 miles from Chicago Heights, Slykas said demonstrators could drive themselves to the southern suburb for treatment, if central city hospitals are overwhelmed.

The Lincoln-Way North High School students worked with Saint James as part of their work in the anatomy and physiology curriculum, which has started many students on the road to careers in medicine.